Stability evaluation of the Gümüşhane-Akçakale cave by numerical analysis method

The Akçakale Cave is located in the vicinity of the Arsa neighborhood within the boundaries of the Akçakale village, Gümüşhane, Turkey. The cave is rich in cave formations (stalactite, stalagmite, cave pearl, cave flower, wall travertines). Thus, the appropriateness of opening the cave to visitors to boost tourism is of importance for the local and national economy. This study analyzes the stability of the Akçakale Cave using a numerical analysis method. According to the results of the total displacement analysis, there are displacements in the entrance, ceiling, and sidewalls of the cave ranging from 1 mm to 48 mm. It seems that the entrance, ceiling, and sidewalls of the cave face a high risk of local or sudden collapse. According to the deformation analysis of the length section of the cave examined, local collapses may occur especially in the first 75 m from the entrance of the cave. We believe that this situation would not carry a risk for the Arsa neighborhood for now. In conclusion, the results of the stability analysis and in-situ observations showed clear evidence of former and ongoing cave-ins (collapses) and the Akçakale Cave faces a high risk of local or sudden collapse. Thus, although the Akçakale Cave is one of the most prominent karst caves in Turkey, it seems to be not appropriate to open the cave to tourist visits.